Add option for set cache policy based on cookie name or pattern

Fixes tempesta-tech#1544

Signed-off-by: Aleksey Mikhaylov <aym@tempesta-tech.com>

Author: ttaym

.gitignore

@@ -23,6 +23,9 @@ Module.symvers
 .settings
 .pydevproject
 
+# vscode project settings
+.vscode
+
 # Python compiler cache files
 *.pyc
 

fw/cache.c

@@ -356,6 +356,10 @@ tfw_cache_employ_req(TfwHttpReq *req)
 	/* cache_fulfill - work as usual in cache mode. */
 	BUG_ON(cmd != TFW_D_CACHE_FULFILL);
 
+	/* No cache for request due to http chain '$cache' action */
+	if (req->cache_ctl.flags & TFW_HTTP_CC_CHAIN_NO_CACHE)
+		return false;
+
 	if (req->cache_ctl.flags & TFW_HTTP_CC_NO_CACHE)
 		/*
 		 * TODO: RFC 7234 4. "... a cache MUST NOT reuse a stored

fw/http.c

@@ -4010,7 +4010,7 @@ tfw_http_hdr_split(TfwStr *hdr, TfwStr *name_out, TfwStr *val_out, bool inplace)
 
 		val_out->len += chunk->len;
 
-		/* 
+		/*
 		 * Skip OWS after the header value (RWS) - they must be in
 		 * separate chunks too.
 		 */
@@ -5402,6 +5402,11 @@ tfw_http_req_process(TfwConn *conn, TfwStream *stream, const TfwFsmData *data)
 	 */
 	req->cache_ctl.timestamp = tfw_current_timestamp();
 	req->jrxtstamp = jiffies;
+	/*
+	 * Bypass cache if corresponding binary flag in request set
+	 */
+	if (unlikely(test_bit(TFW_HTTP_B_CHAIN_NO_CACHE, req->flags)))
+		req->cache_ctl.flags |= TFW_HTTP_CC_CHAIN_NO_CACHE;
 
 	/*
 	 * Run frang checks first before any processing happen. Can't start

fw/http.h

@@ -133,6 +133,7 @@ enum {
 #define TFW_HTTP_CC_MAX_STALE		0x00000010
 #define TFW_HTTP_CC_MIN_FRESH		0x00000020
 #define TFW_HTTP_CC_OIFCACHED		0x00000040
+#define TFW_HTTP_CC_CHAIN_NO_CACHE	0x00000080
 /* Response only CC directives. */
 #define TFW_HTTP_CC_MUST_REVAL		0x00000100
 #define TFW_HTTP_CC_PROXY_REVAL		0x00000200
@@ -263,6 +264,8 @@ enum {
 	TFW_HTTP_FLAGS_REQ,
 	/* Sticky cookie is found and verified. */
 	TFW_HTTP_B_HAS_STICKY	= TFW_HTTP_FLAGS_REQ,
+	/* Request fitted no cache cookie rule */
+	TFW_HTTP_B_CHAIN_NO_CACHE,
 	/* Request is non-idempotent. */
 	TFW_HTTP_B_NON_IDEMP,
 	/* Request stated 'Accept: text/html' header */